S15 trans in s13

[stevecorrado88]

S13 sr20det here my questions I have the s15 flywheel what clutch do I use ( I read u can use s13 sr20det clutch) is that true and sprung or un sprung ? I don't care about speed sensor, I don't have the shifter but I tested a s13 one and it seems to work fine and what driveshaft do I need? I have the piece that goes in the trans but it doesn't look like it will go on my s13 one piece. I'm running about 380hp I get people say they are not strong but I want to try it.

[Mikester]

Pretty sure there is a sticky about it: http://zilvia.net/f/tech-talk/362303-s15-6-speed-transmission-dummies.html

[stevecorrado88]

I read it already, want to see what others say and for the driveshaft it doesn't say much but just a new one.

[Croustibat]

"Others" say "dont do it", which is basically the reason you wont find any info about it.

standard 5 spd transmission is already near its limit on a 380hp SR, sticking a 6spd here just to kill it is somewhat really stupid but hey ... it is your money after all.

I know you ricer guys would love to say "hey i got a fancier gearbox than yours", but these engine have torque. They dont need 6 spd boxes. You want to look cool in the ricer crowd ? Get an os giken 5 gear kit with the input shaft. Or better, a PPG dogbox.

But the S15 6spd ? You will just look stupid (and broke)

[stevecorrado88]

"Others" say "dont do it", which is basically the reason you wont find any info about it.

standard 5 spd transmission is already near its limit on a 380hp SR, sticking a 6spd here just to kill it is somewhat really stupid but hey ... it is your money after all.

I know you ricer guys would love to say "hey i got a fancier gearbox than yours", but these engine have torque. They dont need 6 spd boxes. You want to look cool in the ricer crowd ? Get an os giken 5 gear kit with the input shaft. Or better, a PPG dogbox.

But the S15 6spd ? You will just look stupid (and broke)

Have u even done the swap? Do u no anyone thats done it?? If not u have no say or input on the way I feel. I got all the stuff listed up above for free so far no money has been spent. It's people like u that make this forum suck sonetimes.

[Kingtal0n]

If you drive the six speed nice, and dont try to spin the tires dump the clutch rag on it constantly around corners and gently boost each gear, it will survive behind a 400 horsepower sr20.

[stevecorrado88]

Have u had one break on u? I'm going to be going to events so I will test and we will see how weak they are.

[Mikester]

According to the guy who wrote that sticky, they are awesome for road racing. If you got everything for free; I personally am jealous and wish you the best of luck with your swap... Also, if there is nothing about which driveshaft will work... and you happen to find out, you may want to add to that thread like the OP of it requested. Worse case, he has done a few S15 trans swaps; maybe PM him and see if he will answer- I guarantee he knows.,

[stevecorrado88]

According to the guy who wrote that sticky, they are awesome for road racing. If you got everything for free; I personally am jealous and wish you the best of luck with your swap... Also, if there is nothing about which driveshaft will work... and you happen to find out, you may want to add to that thread like the OP of it requested. Worse case, he has done a few S15 trans swaps; maybe PM him and see if he will answer- I guarantee he knows.,


Thank u for the positive comment.

[oni jake]

Hey buddy,

I bought a S15 motor set back in 08' and used the 6-speed for 2 1/2 years until I roasted the clutch. I switched over to 5-speed setup because finding and installing a flywheel, clutch, trans, and driveshaft was actually cheaper than finding just a S15 replacement clutch.

The S15 comes with a dual-mass flywheel from the factory and is quiet a bit thicker than the S13/S14 flywheel. This means the pressure plates have different heights to match where the throw-out bearing should be. S15 clutches are specific, and with such a low demand new ones cost 2x or 3x more expensive than their S13/S14 counterparts.

If you plan on drifting it, keep the dual-mass flywheel with a sprung clutch, or you will be extremely sad within the first few clutch kicks. These transmissions are weak as fuck, and its only because the gears are physically smaller. No amount of the right transmission fluid or pussy-footing can change the fact that the gears themselves are smaller and weaker than the S13/S14 trans.

If you got this setup for free/cheap, turn around and sell it for immediate profit. Don't waste your time with this headache when there are far better and possibly cheaper transmission/clutch options.

[Croustibat]

OP > I broke a 5spd gearbox with less than 300HP. Friend of mine keeps munching one or two per year, but hes got a 400++HP CA18.

The 6spd gearbox has a small casing, meaning the gears are even smaller than the 5spd, and there is no miracle sturdiomium alloy in the S15 gearbox. Smaller = weaker, and that is it.

So no, i did not break an S15 gearbox. Because i lack the stupidity to install something weaker than what i already broke once. I dont need to DO something stupid to KNOW it is stupid. Did you ever skydive without a parachute ? Of course not, that is stupid and you know it without even trying. See ?

Now go on, spend cash on a custom driveshaft, spend 10+ hours installing all that, and never, never, never come back here crying when it breaks, because i can tell you i will be there to laugh at you.


Kingtal0n > Why didn't i find that by myself ? "if you dont use your engine power then your gearbox wont break". Wow. Thanks for the tip. Oh, wait ... if someone does not want to use nearly twice the OEM power, why would he even tune his engine to that power level ? Nah, can't be because he plans on using it. Why would anyone build a 400HP engine just to use half of it ? You tell me captain obvious.

[stevecorrado88]

I'm pretty sure the casing is bigger but I understand the gears are smaller. Your telling me that everyone that owns s15 that they change the trans out?? I'm gonna say no I garrentee that there are high hp s15 on stock trans. The hole point of this post is to see what needs to be done to install this, I asked about the driveshaft because if I can just swap the part that splines into the trans then I don't need to spend money because I have it all. If it takes you 10+ hours to instal a tranny u work really slow. Y are u argueing with me and y would I bother cry that I broke u its not a big deal nobody will buy it do I might as well break it.

[Croustibat]

Whatever. Your time, your car, your money. I am done trying to put some sense into your head. Do whatever you want.

[oni jake]

Your telling me that everyone that owns s15 that they change the trans out??

Yup, that's basically what's going on. It doesn't happen immediately, and there are people with your train of thoughts hoping for the best. The only thing you can do is retain the stock dual-mass flywheel with a sprung clutch disc.

I'm gonna say no I garrentee that there are high hp s15 on stock trans.

No, no you can't. If you want a 6-speed, do it, but be careful about sticking your own foot in your ass with rebuttals.

[stevecorrado88]

I guess thanks for the feed back but no body really answered any of the questions I asked.

[oni jake]

I guess thanks for the feed back but no body really answered any of the questions I asked.

Some questions have been answered, but for drive shaft stuff.... not sure. I got lucky and had the driveshaft from the motor set. As far as I'm aware, the driveshaft is specific to the 6-speed trans only. There are no other replacements.

[fliprayzin240sx]

Have u had one break on u? I'm going to be going to events so I will test and we will see how weak they are.

I broke 2 of them at 360hp on a greddy T518Z turbo...yes they fucking suck, specially when you have a twin plate clutch hooked up to it. I stopped blowing SR trannies (both 5-speed and 6-speed) when I swapped in an RB25 tranny.

[Kingtal0n]

OP >

Kingtal0n > Why didn't i find that by myself ? "if you dont use your engine power then your gearbox wont break". Wow. Thanks for the tip. Oh, wait ... if someone does not want to use nearly twice the OEM power, why would he even tune his engine to that power level ? Nah, can't be because he plans on using it. Why would anyone build a 400HP engine just to use half of it ? You tell me captain obvious.

I think you misunderstand the different ways in which a person might want to use a transmission.

Some of us just want to daily driver it. In a daily driver, it will be difficult to break an S15 transmission even at 500 horsepower.

Others want to drift/drag. To that, I say this:
I can break any OEM transmission in any vehicle if you give me some slicks and a twin plate clutch, even if it only has 200 horsepower. The power level does not matter nearly as much as the intended usage.